IBM 000-8697 Manual Do Utilizador

Data Consistency, Recovery, and Migration

Set the

DUMPCORE

 environmental variable as an alternative to

GCORE

 for

systems that do not support the gcore utility.

DUMPCORE

 directs each

OnLine database server process to dump core when it detects an inconsis-
tency or initiates an abort sequence. To accomplish this, the server process
sends itself a segmentation violation signal. The result, which is a terminated
process that requires cleanup by an OnLine daemon process, is less elegant
than the

GCORE

 option.

If you mistakenly set both

GCORE

 and

DUMPCORE

, the server process first

calls gcore, dumps core, then continues until the

DUMPCORE

variable directs

the process to dump core again and send itself a segmentation violation
signal.

If

DUMPCORE

 is set, you risk OnLine aborting whenever a user process

detects an inconsistency while it is in a critical section or holding a latch.

Set the

DUMPCORE

 environment variable at the system prompt or in your

 or .cshrc (C shell) or your .profile (Bourne shell) file as follows:

The

DUMPSHMEM

environment variable directs the OnLine database server

process to save a copy of shared memory to a file in the current directory or
the directory specified by

DUMPDIR

.

The filename takes the format shmem.pid.cnt. The pid value is the OnLine
database server process identification number. The cnt value is incremented
each time this process encounters an inconsistency. The cnt value can range
from 1 to 4. After 4 copies of shared memory are saved to separate files, no
more files are created. If the server process continues to detect inconsistencies
in this section of code, errors are reported to the OnLine message log (and
perhaps to the application), but no further diagnostic information is saved.

setenv DUMPCORE

DUMPCORE =

export DUMPCORE